Diagnosing Controller w/ Ebike Tester

General Discussion about electric bicycles.
Post Reply
ebikedreamin   100 µW

100 µW
Posts: 8
Joined: May 02 2020 1:33pm

Diagnosing Controller w/ Ebike Tester

Post by ebikedreamin » May 02 2020 1:40pm

Hey All -

I'm trying to figure out what's wrong with my ebike and I've hit a wall - hoping someone here could point in the right direction. My ebike isn't turning on and so I bought an ebike tester and it looked like the problem was the controller - everything else tested and was working but no lights with the controller. So I bought another controller - but the same thing happens, no lights. I've tested the motor, throttle, brakes, and the battery voltage - they all look good.

Is it possible I have two broken controllers? Is there anything else I can try?

Thanks!

Mike

goatman   100 MW

100 MW
Posts: 2677
Joined: Jun 23 2019 6:50pm
Location: Surrey, B.C.

Re: Diagnosing Controller w/ Ebike Tester

Post by goatman » May 02 2020 3:57pm

if you upload pictures it helps, new controller blown? anythings possible. exact same controller?
whats not lighting up, the display?

you haven't changed your battery recently right?

ebikedreamin   100 µW

100 µW
Posts: 8
Joined: May 02 2020 1:33pm

Re: Diagnosing Controller w/ Ebike Tester

Post by ebikedreamin » May 02 2020 6:29pm

I'll upload pictures shortly but yeah the second controller is the same model. Using the ebike tester with the controller and throttle, i'm not getting any of the AABBCC lights which I think are supposed to flash and spin in a circle when you turn the throttle. I haven't changed the battery recently, but the battery charge indicator light stopped working around the same time. The voltage coming out of the battery looks good though so I think the battery is good.

goatman   100 MW

100 MW
Posts: 2677
Joined: Jun 23 2019 6:50pm
Location: Surrey, B.C.

Re: Diagnosing Controller w/ Ebike Tester

Post by goatman » May 02 2020 6:46pm

is the battery charge indicator light part of the throttle or on the battery. maybe you blew a fuse inside the battery case or in the bms but PICTURES :D someone might help you.

docw009   100 kW

100 kW
Posts: 1379
Joined: Aug 02 2015 7:43am
Location: Chicago area suburbs.

Re: Diagnosing Controller w/ Ebike Tester

Post by docw009 » May 02 2020 11:03pm

When you plugged the controller into the tester did the center led light up in middle of the circular group of 6 led's? If you don't see that, there's no 5V power running the Hall sensors in the 2x3 molex plug.

You can check the red and black wire on that same plug with a voltmeter to verify.

If there's no 5 volt power on both the new and old controller, it's more likely that whatever turns on your controller, a handlebar switch attached to the LCD or LED, or a switch attached to the throttle ...those switches or the wire harness are not working to turn on your controller (new or old).

Since you haven't described your bike, you have to post some pics, including some that shows how the bike turns on, Maybe the connector from the display or throttle too. Then you might get some help tracing the circuit that turns on the controller to makes sure it works.

User avatar
amberwolf   100 GW

100 GW
Posts: 31747
Joined: Aug 17 2009 6:43am
Location: Phoenix, AZ, USA, Earth, Sol, Local Bubble, Orion Arm, Milky Way, Local Group
Contact:

Re: Diagnosing Controller w/ Ebike Tester

Post by amberwolf » May 02 2020 11:15pm

Are you measuring the battery voltage while it is connected to the controller?

Or when it is not connected to anything?

The former should give a correct reading. The latter may appear correct, but in actuality be leakage thru the shut-off output of the BMS, which will go away once a load is placed on it.

ebikedreamin   100 µW

100 µW
Posts: 8
Joined: May 02 2020 1:33pm

Re: Diagnosing Controller w/ Ebike Tester

Post by ebikedreamin » May 03 2020 12:38am

Thanks for the replies! The battery indicator that no longer works was part of the battery itself. If the BMS is the problem on the battery would you still be able to read a voltage? I was taking the reading from the battery directly - which wires would give you the voltage from the controller?

I attached a picture of my testing setup. The 5v light is in a different place - but it wasn't lighting up either. I'm also using a new throttle - one that only has 3 wires (red/black/green) instead of 6 and no on/off switch like the previous one. Seems like that might be the issue?
IMG_3271 copy.jpg
IMG_3271 copy.jpg (237.6 KiB) Viewed 383 times

docw009   100 kW

100 kW
Posts: 1379
Joined: Aug 02 2015 7:43am
Location: Chicago area suburbs.

Re: Diagnosing Controller w/ Ebike Tester

Post by docw009 » May 03 2020 1:57am

Yikes. You gotta replicate the on off switch. The old one had six wires?

One is going to be your battery power. Another one will probably get switched to battery power when the on/off is switched, I don't know what the third one would do. A picture of your throttle is needed.

Connect the old throttle back up and turn it on. Use your voltmeter to find the battery wire and also to find the second wire that gets switched to power. To keep your controller turned on, jumoing those two wires should do it. You could add a switch too.

.

John in CR   100 GW

100 GW
Posts: 15099
Joined: May 20 2008 12:58am
Location: Paradise

Re: Diagnosing Controller w/ Ebike Tester

Post by John in CR » May 04 2020 2:53am

docw009 wrote:
May 03 2020 1:57am
Yikes. You gotta replicate the on off switch. The old one had six wires?

One is going to be your battery power. Another one will probably get switched to battery power when the on/off is switched, I don't know what the third one would do. A picture of your throttle is needed.

Connect the old throttle back up and turn it on. Use your voltmeter to find the battery wire and also to find the second wire that gets switched to power. To keep your controller turned on, jumoing those two wires should do it. You could add a switch too.
+1 You probably have 2 good controllers and just weren't turning them on. To verify it is turning on, measure to see if about 5V is going to the throttle. If the throttle is getting voltage, then check that your battery voltage is within the operating range of the controller, ie less than the high voltage cutoff and more than the low voltage cutoff. If that's not the issue, then make sure the ebrake cutoff isn't the issue.

Did you check the motor phases and hall sensors with the tester, as well as the throttle? I like to do the easy stuff first while going through the process of elimination to find problems.

ebikedreamin   100 µW

100 µW
Posts: 8
Joined: May 02 2020 1:33pm

Re: Diagnosing Controller w/ Ebike Tester

Post by ebikedreamin » May 05 2020 9:12pm

When I measure the throttle from the controller plugged into the tester I get 4.8V going to the throttle. I think i've tested the battery voltage as well and it was coming up around 30V - i'm going to double check that. Also tested the motor hall sensors and that seems to be working too.

Yeah the last throttle had six wires - that throttle definitely is broken so sadly I can't use it to test. I ordered another throttle with an on/off switch that should be here soon though - hopefully that's the issue. Thanks again for the super helpful info!

ebikedreamin   100 µW

100 µW
Posts: 8
Joined: May 02 2020 1:33pm

Re: Diagnosing Controller w/ Ebike Tester

Post by ebikedreamin » May 11 2020 8:02pm

Well I got a new throttle with an on/off switch but it appears I got a lemon. Does this throttle wiring look correct to you guys? I'm wondering if maybe the colors on the controller and tester wires are different than the throttle. Otherwise I'm gonna send this one back and get a replacement.
61gG3T-6YtL._AC_SX679_.jpg
61gG3T-6YtL._AC_SX679_.jpg (29.71 KiB) Viewed 222 times

ebikedreamin   100 µW

100 µW
Posts: 8
Joined: May 02 2020 1:33pm

Re: Diagnosing Controller w/ Ebike Tester

Post by ebikedreamin » May 16 2020 11:44am

Okay so I got a replacement throttle that works and I connected and tested everything. I found out I was not testing the controller correctly in the first place - apparently you need to have the battery connected in order for the testing device to work - you can't test the controller alone. At any rate when connecting the battery to the controller and then to the tester - I'm not actually getting 5v from the controller. Does that mean the controller is busted? Maybe I just got a lemon of a replacement?

A summary of what i've learned so far:

1. You need to have the battery connected to the controller in order to test the controller
2. There is a 5v light on the tester that should light up when connecting the controller/battery to the tester
3. Some controllers need to be turned on before you can use them, so testing a throttle without an on/off switch won't work if you have that kind of controller (which I do)
4. Controllers and throttles have different wiring configurations (unless they come in a package) and you'll need to look at a wiring diagram to figure out which connectors go where

This is the tester being used
https://www.ebay.com/itm/24V-36V-48V-60 ... -Tester-US

Firedog   10 W

10 W
Posts: 67
Joined: May 26 2017 10:23pm

Re: Diagnosing Controller w/ Ebike Tester

Post by Firedog » May 16 2020 1:00pm

30v battery voltage? That's below the LVC on many 36v controller.

ebikedreamin   100 µW

100 µW
Posts: 8
Joined: May 02 2020 1:33pm

Re: Diagnosing Controller w/ Ebike Tester

Post by ebikedreamin » May 16 2020 1:56pm

I just measured it again and i'm getting 40v - not sure what was going on before or if that was a typo

Post Reply